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- Definition

Employee Stock Purchase Plan, Purchase Price Lock-in Period (months)

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Annual Vesting Rate

+ References

No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award, award contractual term

+ References

No definition available.

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- Definition

Percentage of market price employees pay for Company stock purchased under the Employee Stock Purchase Plan.

+ References

No definition available.

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

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-Number 123R

-Paragraph A240

-Subparagraph h

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Paragraph 2

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The addition or reduction in the number of reserved shares that could potentially be issued under the option plan attributable to reasons other than grants, exercises, forfeitures, and expirations during the reporting period.

+ References

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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-Name Regulation S-X (SX)

-Number 210

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Stock-Based Compensation (Narrative) (Details) (USD $)	0 Months Ended	12 Months Ended
Stock-Based Compensation (Narrative) (Details) (USD $)	Apr. 02, 2013	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Share Based Compensation [Line Items]
Total intrinsic value of stock options exercised		$ 125,100,000	$ 56,900,000	$ 31,400,000
Employee Stock Purchase Plan, Purchase Price Lock In Period		12 months
Stock Option [Member]
Share Based Compensation [Line Items]
Increase in shares available for issuance, stock option plan		4,000,000
Shares authorized		11,600,000
Shares available for issuance		5,000,000
Weighted-average grant date fair value of stock options granted		$ 29.40	$ 22.78	$ 22.72
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term		4 years 8 months
Unrecognized compensation expense related to non-vested stock options		38,200,000
Weighted-average vesting period of non-vested stock options (in years)		1 year 8 months
Exercised, Number Of Stock Options		2,423,265	1,253,672	812,304
Option Grants after April 1, 2006 [Member]
Share Based Compensation [Line Items]
Annual vesting percentage		25.00%
Terms of awards		maximum term of eight years
Share-based compensation arrangement by share-based payment award, award contractual term		8 years
Option Grants before April 1, 2006 [Member]
Share Based Compensation [Line Items]
Annual vesting percentage		25.00%
Terms of awards		maximum term of ten years
Share-based compensation arrangement by share-based payment award, award contractual term		10 years
Employee Stock Purchase Plan [Member]
Share Based Compensation [Line Items]
Shares authorized		5,500,000
Shares available for issuance		1,600,000
Weighted-average grant date fair value of stock options granted		$ 16.73	$ 13.16	$ 16.05
Exercised, Number Of Stock Options	62,137	261,193	282,947	338,037
Annual gross earnings withheld, maximum		15.00%
Percentage of market price employees pay for Company stock in ESPP		85.00%
Employee Aggregate Annual Purchase Limit Maximum		$ 25,000